U.S. Bald Eagles Have Widespread Lead Poisoning, Study Finds

Bald eagles across the United States have widespread and frequent lead poisoning, according to a recent study.

In a study published on Feb. 17 in the journal Science, researchers said they detected high rates of lead poisoning in bald and golden eagles from 2010 to 2018, impacting both species’ populations.

Of the studied 1,210 bald and golden eagles from over 38 U.S. states, 46% of bald eagles and 47% of golden eagles had chronic lead poisoning.

According to the researchers, lead poisoning in eagles typically occur when they eat lead fragments from bullets lodged inside animal carcasses left behind by hunters.

“Every single time a lead bullet hits a deer, it fragments into many, many pieces. It only takes a tiny fragment, something the size of the head of a pin, to kill an eagle,” Todd Katzner, a U.S. Geological Survey wildlife biologist and co-author of the study, told Insider.

The study found that the poisoning at the levels is causing population growth rates for bald eagles to slow by 3.8% and for golden eagles by 0.8% annually.

U.S. Fish and Wildlife Service National Raptor Coordinator Brian Millsap, who is also a co-author of the study, said that the reduction of the population growth for bald eagles was not “impactful” because the species’ population grows by 10% annually across the U.S.

However, Millsap warned that the golden eagle’s population was “not as stable, and any additional mortality could tip it towards a decline.”

The study is the first to examine bald and golden eagle populations across North America. Similar studies were previously only performed locally and regionally.

“Now that we have evidence that lead is affecting eagles nationwide, we are poised to address this problem,” Dr. Vince Slabe, lead author on the study, said.


© Fourth Estate® — All Rights Reserved.
This material may not be published, broadcast, rewritten or redistributed.